This invention relates to oxidized normal paraffinic products. In particular this invention relates to said products and their application as flotation agents in, for example, minerals beneficiation, as well as in lubricants and drilling muds.
Mixed fatty acids are obtainable from vegetable extraction or mammal is fat and lard. Natural fatty acids are of diverse sources and the composition and the saturation varies depending on the source of the material. The said natural organic compounds have various industrial applications such as flotation agents, in the production of detergents, as a wetting agent for insecticides, as synthetic lubricants in water-soluble applications and when esterified, as water soluble lubricants in drilling mud applications.
It is known in the art that natural organic carriers can be used in mineral flotation applications. One such natural fatty acid is oleic acid. This product is highly unsaturated and its composition varies.
It is known that unsaturation in the organic compound causes a large amount of gangue minerals to float together with the desired ore component. Therefore, a low purity rough concentrate will be obtained. This necessitates reflotation of the collected material using additional amounts of depressant. It can therefore be concluded, that the higher the degree of unsaturation the more tedious and costly the beneficiation process becomes.
It is also known that if the purity of the fatty acid is low and of varying composition, the recovery of the desired ore component will be lower and more unpredictable respectively, than expected, The ground ore will have to be refloated adding more collectors until the expected recovery is achieved.
The beneficiating process will again be less efficient the lower the purity and the more the composition of different batches of natural fatty acid varies.
Although the benefaction processes that are known in the art, and using the said natural products are effective, there nevertheless continues to exist the need for new processes and materials. In particular the disadvantage associated with the naturally obtained fatty acid products, i.e. the inconsistency of product composition and the purity that causes problems in formulating the dosages for the beneficiating process and the high degree of unsaturation present in the natural products that affects the flotation negatively (lower activity) that require higher dosage levels need to be addressed.
The inventors have now surprisingly found that by oxidizing a synthetically derived saturated hydrocarbon composition a final product of industrial grade can be obtained. Said product comprises a highly saturated fatty acid of known composition that also contains saturated alcohols. The product of the invention eliminates the disadvantages encountered in conventional applications with saturation and varying composition. The product of the present invention furthermore, has greater stability and longer life due to comparatively slower bio-degeneration.
According to a first aspect of the invention there is provided a flotation agent including an oxidised paraffinic product.
The paraffinic product may be a Fischer-Tropsch reaction product obtained by way of the Fischer-Tropsch reaction from CO (carbon monoxide) and H2 (hydrogen) feed.
The paraffinic product may be Waksol(trademark) obtainable from Schumann-Sasol.
According to a second aspect of the invention there is provided a process for the production of a synthetic fatty acid suitable as a substitute for naturally derived fatty acids In various applications.
In one embodiment of the invention the synthetic fatty acid may be applied in the beneficiation of minerals such as calcium fluoride, phosphate and coal.
The beneficiating process may comprise froth flotating a pulp conditioned with gangue metal depressant, where necessary and using the said synthetic fatty acid as a flotation and/or froth collecting agent.
The synthetic fatty acid may also be suitable for use as a synthetic lubricant in water-soluble lubricant applications. When esterified the synthetic fatty acid may be used as a water-soluble lubricant for drilling mud applications. When saponified with inorganic salts especially Calcium Hydroxide or esterified with various alcohols the product may be used as a corrosion protection agent.
According to a third aspect of the invention there is provided a minerals beneficiation process including the use of a synthetic fatty acid substantially as described above.
The minerals beneficiation process may be for the beneficiation of mineral ores containing phosphate, fluorspar and coal using oxidized Waksol as flotation agent.
The invention extends to the oxidation of Waksol, a commercial product of Schumann-Sasol (SA) Pty Ltd, having the physical and chemical properties as given in Example 1.
The oxidation of Fischer-Tropsch wax using standard oxidation processes and the properties and specification of the oxidized products which are suitable for the applications are given in Example 2.
The invention extends to the use of the oxidized Waksol as a synthetic water-soluble lubricant.
Without in any way limiting the invention, typical upper and lower limits of the process conditions useful for performing the invention as well as the values used are defined in the examples.
The present invention finds application in various fields, however, the list below is not exhaustive and is not intended to limit the scope of the invention. It will be dear to those skilled in the art that the Invention also has further applications.
Oxide mineral beneficiation by means of flotation concentration
Coal beneficiation by means of flotation concentration
Production of synthetic water soluble lubricants
Corrosion protection by forming a thin metal adhesive film
Conventional applications of the applications listed above use mixed fatty acids obtained from the extraction of vegetation of mammal fat or lard. These materials are of low acid value and needs to be further oxidized to the desired acid number.
Some of the benefits of the synthetic fatty acid obtained from the invention are:
Low relative degree of unsaturation when compared to the currently used fatty acids. The high degree of unsaturation render these natural fatty acids prone to flotation of gangue minerals which require higher dosages of gangue metal depressants than needed for the products of the invention. Higher purity resulting in a lower required dosage level. The lower purity of the fatty acids from natural origin render them less active resulting in higher required dosage for similar yields to the those of the products of the invention.
Lower biodegradation greater stability and longer shelf life when compared to the fatty acids from natural origin currently used in these technologies.
The water soluble lubricants from these products require less emulsion enhancing and stabilizing additives producing products with enhanced friction coefficients when compared to those currently used.
The corrosion protectors from these products have excellent adhesion to metal surfaces, good film forming ability and superion emulsifiality and lubricating properties.
The products of the invention can be applied in lubricants, as it also contains esters that are known to aid lubrication, in drilling fluids and as a froth collector in froth flotation applications and as corrosion protection agents.
Other specific advantages when applying the product of the present invention includes the high degree of saturation requiring lower dosage levels when compared to the known, high level unsaturated natural fatty acids.
In the water soluble lubricant applications, less emulsion stabilizing additives and emulsifiers are needed when using the product of the invention as compared to known technology.
In corrosion protection, providing both lubrication and rust prevention and because of the thin film ability, less product is applied when compared to conventional products.